/*
 * Copyright 2002-2018 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.transaction.interceptor;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.lang.Nullable;
import org.springframework.util.ClassUtils;
import org.springframework.util.ObjectUtils;
import org.springframework.util.PatternMatchUtils;

import java.io.Serializable;
import java.lang.reflect.Method;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;
import java.util.Properties;

/**
 * Simple {@link TransactionAttributeSource} implementation that
 * allows attributes to be matched by registered name.
 *
 * @author Juergen Hoeller
 * @see #isMatch
 * @see MethodMapTransactionAttributeSource
 * @since 21.08.2003
 */
@SuppressWarnings("serial")
public class NameMatchTransactionAttributeSource implements TransactionAttributeSource, Serializable {

    /**
     * Logger available to subclasses.
     * <p>Static for optimal serialization.
     */
    protected static final Log logger = LogFactory.getLog(NameMatchTransactionAttributeSource.class);

    /**
     * Keys are method names; values are TransactionAttributes.
     */
    private Map<String, TransactionAttribute> nameMap = new HashMap<>();


    /**
     * Set a name/attribute map, consisting of method names
     * (e.g. "myMethod") and TransactionAttribute instances
     * (or Strings to be converted to TransactionAttribute instances).
     *
     * @see TransactionAttribute
     * @see TransactionAttributeEditor
     */
    public void setNameMap(Map<String, TransactionAttribute> nameMap) {
        nameMap.forEach(this::addTransactionalMethod);
    }

    /**
     * Parses the given properties into a name/attribute map.
     * Expects method names as keys and String attributes definitions as values,
     * parsable into TransactionAttribute instances via TransactionAttributeEditor.
     *
     * @see #setNameMap
     * @see TransactionAttributeEditor
     */
    public void setProperties(Properties transactionAttributes) {
        TransactionAttributeEditor tae = new TransactionAttributeEditor();
        Enumeration<?> propNames = transactionAttributes.propertyNames();
        while (propNames.hasMoreElements()) {
            String methodName = (String) propNames.nextElement();
            String value = transactionAttributes.getProperty(methodName);
            tae.setAsText(value);
            TransactionAttribute attr = (TransactionAttribute) tae.getValue();
            addTransactionalMethod(methodName, attr);
        }
    }

    /**
     * Add an attribute for a transactional method.
     * <p>Method names can be exact matches, or of the pattern "xxx*",
     * "*xxx" or "*xxx*" for matching multiple methods.
     *
     * @param methodName the name of the method
     * @param attr       attribute associated with the method
     */
    public void addTransactionalMethod(String methodName, TransactionAttribute attr) {
        if (logger.isDebugEnabled()) {
            logger.debug("Adding transactional method [" + methodName + "] with attribute [" + attr + "]");
        }
        this.nameMap.put(methodName, attr);
    }


    @Override
    @Nullable
    public TransactionAttribute getTransactionAttribute(Method method, @Nullable Class<?> targetClass) {
        if (!ClassUtils.isUserLevelMethod(method)) {
            return null;
        }

        // Look for direct name match.
        String methodName = method.getName();
        TransactionAttribute attr = this.nameMap.get(methodName);

        if (attr == null) {
            // Look for most specific name match.
            String bestNameMatch = null;
            for (String mappedName : this.nameMap.keySet()) {
                if (isMatch(methodName, mappedName) &&
                        (bestNameMatch == null || bestNameMatch.length() <= mappedName.length())) {
                    attr = this.nameMap.get(mappedName);
                    bestNameMatch = mappedName;
                }
            }
        }

        return attr;
    }

    /**
     * Return if the given method name matches the mapped name.
     * <p>The default implementation checks for "xxx*", "*xxx" and "*xxx*" matches,
     * as well as direct equality. Can be overridden in subclasses.
     *
     * @param methodName the method name of the class
     * @param mappedName the name in the descriptor
     * @return if the names match
     * @see org.springframework.util.PatternMatchUtils#simpleMatch(String, String)
     */
    protected boolean isMatch(String methodName, String mappedName) {
        return PatternMatchUtils.simpleMatch(mappedName, methodName);
    }


    @Override
    public boolean equals(Object other) {
        if (this == other) {
            return true;
        }
        if (!(other instanceof NameMatchTransactionAttributeSource)) {
            return false;
        }
        NameMatchTransactionAttributeSource otherTas = (NameMatchTransactionAttributeSource) other;
        return ObjectUtils.nullSafeEquals(this.nameMap, otherTas.nameMap);
    }

    @Override
    public int hashCode() {
        return NameMatchTransactionAttributeSource.class.hashCode();
    }

    @Override
    public String toString() {
        return getClass().getName() + ": " + this.nameMap;
    }

}
